Their senseless deaths "awakened the slumbering consciousness of America and galvanized the civil rights movement," Alabama Rep. Terri Sewell said at the Congressional Gold Medal ceremony at the U.S. Capitol.

"Fifty years later, we finally honor their life and legacy. Justice delayed but not denied," Sewell said.

At the ceremony, House Speaker John Boehner recalled details of the girls' lives.

Addie Mae went door-to-door after school selling aprons and potholders her mother made. Denise put on skits in the garage to raise money for muscular dystrophy research.

Carole made sure her chores were done so she could go to dance class on Saturdays, while Cynthia excelled in math and band.

"Birmingham had to go through hell but found its way back and pushed itself forward and pushed the whole country forward as well," Boehner said. "This is one of the true American stories."

Three former Ku Klux Klan members were convicted in the church bombing, which left at least 14 other people injured.

President Barack Obama signed legislation granting the posthumous honor in May.